﻿<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title></title>
    <style type="text/css">
    .div1
    {
        height:500px;
        width:100%;
        background:yellow;
        position: relative;
        display:inline-block;
    }
    .div2
    {
        height:50px;
        background:red;
    }
    .div3
    {
        position:absolute;
        bottom:0px;
        top:50px;
        left:0px;
        right:0px;
        border:1px solid dimgray;
    }
    
    </style>
</head>
<body>
    <div class="div1">
        <div class="div2">
        DIV2
        </div>
        <div class="div3">
        DIV3
        </div>
    </div>
</body>
</html>
